Automatic train control and cab signaling



Oct. 2, 1928. 1,686,036

' H. M. RYDER AUTOMATIC TRAIN CONTROL AND CAB SIGNALING Filed Feb. 5, 1925 2 Sheets-Sheet 1 4a \mms6- 805 402 F/Vfev- 57/?! S INVENTOR x/gV V/ITNESS Harry Ryder ATTORNEY Oct. 2, 1928. l 1,686,036

v H. M. RYDER AUTOMATIC TRAIN CONTROL AND CAB SIGNALING Filed Feb. 5, 1925 2 Sheets-Sheet 77M l/Y Am LINE AIR LINE BA TrERy TOR- WITNESSES: INVEN Harry M Ryder flyda WW 'ATTORNEY Patented Oct. 2, 1928.

A U I D 'ISTATELS PA NT ,O F1 -P HARRY-M. RYDER, or sHARPsBURe; MARYLAND, ASSIGNOR T WESTINGHOUSE nrno- TRIC' & MANUFACTURING ooMr NY,'A conronA'rro osrENNsYLvANIA.

AnTo A'rro' TRAIN coN'rnonANn CAB SIGNALING Application filed February 3, 1925. Serial No. 6,551. i

My invention relates to automatic traini control systems and signaling devices.

One object of my invention is to provide a system o f'con'trol for a railwayvehiclewherebyit will be impossible for an engineman to run past stop signals. v

Another object of my invention iis'to providenieans for signaling to the engineer the traffic conditions of the track over which the vehicle is operated.

Still another object of my invention is to provide means forstopping a railway vehicle within any block when the next block contains a vehicle traveling over the same track.

7 A further object of my invention is to provide means for energizingthe rails over which a vehicle operates with electrical en- I ergy of difierent frequencies in accordance Fig. 2 is a with 'trafiic conditions. 7

A further object of my invention is to auto- "matically govern the speed of a vehicle in accordance with the frequency of the electrical cur1'ent traversing the rails over which the vehicle travels. r p H Still another object of my invention islto provide means for preventing electrical en; ern'y "from being dissipated through those axles of a vehicle which donot have some part of an "automatic signaling device or control system mounted thereon.

Briefly speaking, my invention comprises the energizing-of the rails of a section of track in accordance withtraliic conditions, and providing means mounted upon a' loco notive and responsive to electrical energy. traversing the rails for governingsignal lights and also a pneumatic valve for controlling the airbrakes of a vehicle; I

My invention also comprises mounting a laminated iron core upon the axles of a. locomotive or motor vehicle for preventing signal currents from traversing parts of vehicles other than the axle or axles that are provided with a mechanism adapted to operate the signal devices. y I i Reference may non-be made to the acco npanying drawings, Figure 1 ofwhich is a diagrammatic view partly inplan and partly in side elevation of several sections of: track with the wheels of arailway vehicle mounted thereon. The track. is energized with signaling currents by means of electrical devices that will described. v a

. ag fammatic view of the con hereinafter he more fully sections of track, therails ofwhich are energized 1n asomewhat different manner from "suitableinsulatin ple, as wood.

tr'ol system of a vehicle, mounted thereon and I employed to govern th'e'speed of the vehicle 111 accordance with traffic comlitions, This automaticcontrol system for a vehicle also provides means for "automatically signaling v the engineer, concerning the condition. of the Figs. 3 and 4 are views, in side and'in end elevation, respectively, of a laminated iron core 'mou nted uponone of the'axl'es of the vehicle illustrated in Fig. lofthe drawing.

'Fig. 5 is a diagrammaticview or several that of Fig. 1. I

Fig. 6 is a 'diagrammaticyiew ofan automatic train-control system and signaling device of somewhat different construction. from that illustratedin Fig. 2 of the drawings.

Referring particularly to Fig. 1, a track 1 is provided with a plurality of parallel-extending rails 2 thatare-sepa-rated, one from another by a plurality ofsection breaks or insulated ioints 3, which are made from any g material, such, for exam- Fig. 1 showsthree sections of track respectively marked A, B, and C A plurality of relays 4 andAa and a plurality of trans formers 5, 5a, 6 and 6a are provided for governing the energizationpofthe. rails 2. :The rails 2 of the track 1 are'desi-gnated' as the north and the south rails," for the sake of convenience. I Y a 5 A vehicle or train, 7 0$ which onlya small. number of axles 8 and .9 andcorresponding pairs of wheels 10 and '11 are illustrated; is movably mounted on the rails 2.,

' Each of the relays 4 and 4a is provided with a plurality of movablecont act members 12 to 14, inclusive. and with an actuating coil, which is electric-ally. connected to the rails 2 of the corresponding section.

Each of the transforme s 5 and 5a i-spro- V vided with a primary winding 14, a second: ary windingla and a.mag netizable "core member 16. -Ea'ch of the transformers {Sand 60. is provided with a primarywindi-ng 17, a secondary winding 18 and amagn'etizahle core member 19.. r i

formers 5 and 5a are'supplied with electrical energy fa frequency of cycles while the primary windings 17 of thetransftbrane'rs 6 The primary windings 14; of; the trans and 6a are energized from a-source of electrical energ of a frequency of 40 cycles. It

' is to be un erstood, however, that-electrical energy ofdiflerent frequencies than 80 cycles and 40. cycles may be employed for operating my controlsystem without departing from the spirit of my invention.

Each of the axles 8 of the locomotive 7 is rovided with a reactance device 21, which s bestillustrated in Figs. 3 and 4 of the drawing. The reactance device 21 comprises a plurality of laminated flat annular members discs 22 which are made of iron. The discs 22 are separated from the axle 8 by means of a fin 23 which is made of some suitable insulat ng material, such, for example, as

' 'micarta.

The object of mounting the reactance devices 21 upon the axles 8 is to increase the electrical impedance of the circuits comprising the wheels and the axles 8, thereby substan- :tially preventingthe energy that governs the drawing.

signal devices and control apparatus from be- 'ingdissipate'd through those axles. The axle 9 is provided with a transformer 24, which is best illustrated in Fig. 2 of the Referring particularly to Fig. 2 of the drawing. the portion of the locomotive 7 that automatically governs the speed thereof is illustrated herein. 'An air-brake pipe 251s cmloyed to govern the operation of the air-' rakes "(not illustrated) of the vehicle 7.

tatablemember 27, and a stationary, member or casing 28. The stationary member28 is provided with an outlet port '29 that opens into the atmosphere and an inlet port 30 that is directly. connectedto the pipe 25.,

The rotatable member 27 is provided with an air,duct 31, .which is so designed that it may be rotated until it pneumatically vconnects the inletport 30 with the outlet port 29, thereby releasing the fluid under pressure j Within the brake pipe 25. When fluid presis governed by a pluralityof screws36 which -The lever is biased to the position illns-* are 'adjusta'bly mounted in a stationary block 37;

' tratedin Fig. 2 oft-he drawings by means of a resilient member or compression spring 38 which is; compressed against a stationary The brake ,pipe25 is directly connected toa pneumatic valve 26 which comprisesa robracket member 39. When the resilient member SSact-uates the lever 35 to this position, the

lever 32 actuates the rotatable member 27 of l the pneumatic valve device 26 to the position illustrated. The fluid, under pressure, in the brake pipe 25 is thereupon exhausted, through the inlet port-30, ai-r duct 31 and outlet port 29, to the atmosphere. When the air pressure is reducedin the air-brake pipe 25, the brakes (not illustrated) of the vehicle 7 are applied, as previously set forth. v V

The operation of the-rod 34 may also be effected by a magnetizable core member 41' and a plurality of coils 42 and 42a which constitute portions of the electro-magnetic de v vice 33, in a manner hereinafter more fully described. The energization of the coil 42 comprises a plurality of brush members 44 that are connected to the coil 42. The gen-' erator 43 is mechanically connected in any suitable manner,'to an axle 8 of the vehicle 7 to be driven thereby.

is effected by means of a generator 43 which I The generator, 431s so designedthat the voltage across the brushes 44 is directly proportional to the speed of the Vehicle 7. When the speed of the vehicle 7 is relatively high,

V the actuating coil 42Iofthe electrical control device 33 is so energized that it assists the compression spring 38. to actuate the rod34 to the right and, hence, the rotatable membcr 27 of the valve device-26, ina counterclockwise direction,-to efi'ect application of the brakes.

erned by a transformer 45, in a manner hereinafter more fully described. The transformer 45 is provided with a primary wind inn 47, a secondary winding 48 and a mag- Y netizable core member 49.

A resonant device 51, comprising a condenser 52 and a reactance coil ,53, is employed to provide a shunt circuitfor filter'for electrical energy of a frequencyof 80 cycles. An electrical device 54, which coinprises a part of the electrical control device 33, embodies a magnetizable 'core'member 55, that is mechanically connectedto thelever 35, and an actuating coil 56. The energization of the coil 56 is, governed by a transformer 57 which comprises a primary winding 58, a secondary winding 59, and a core member 61. A resonant device 62 comprises a c-ondenser 63 The energization of'the coil 42a is gov-i and a reactance coil 64." The resonant device 62 is employed to provide a shunt circuit or 'filter. across the primary winding 58 ofthe transformer 57 for electrical currentof a frequency of 40 cycles.

The axle transformer 24 is provided with a laminated iron core-65 which is mounted upon a suitably insulated cylindrical member66. A secondary winding v67 'is wound upon the laminated iron core'65. The pri mary winding ofthe transformer .24 comprises the axle 9. The secondary winding 67 eeseoee of the "transformer '24 isconnected in series relation with the primary windingsd7 and '58of'the transformers t and 57, respectively. The axle 9"isenergized by the electrical current traversing the rails 2 of the track'l, as will be understood.

A plurality of signal lamps 68t0 7 0-, in-

clu'sive, are provided for indicating to the cated inlap area, otherwisemeaning that a leading vehicle is located in the same block. The lamps 68 to 70, inclusive, will be referred to as the clear, caution and stop signals, respective1y.. f

A source of electrical energy, such as a headlight generator or a storage battery? 1 is provided for energizing the redla-mp 70.

plurality of relays 7 2 and 7 3 are provided :for governing the energization of the red lamp 70 in a manner hereinafter more fully described.

The actuating coil of the relay 72 isgcon nect'ed in series relation with the gree'nlamp 68. The actuating coil of the relay,73 is connected in series relation with the yellow lamp relay 7 2 or 73 is actuated to its open position and the red lamp 70fis deenergi'zeel. The operation of my automatic traincontrol system is as follows lVhen a vehicle corresponding to'the vehicle 7 occupies track 1 in block B, the actuating coil of the relay 4 is short circui-ted by the axle 9 of vehicle '7, and

j the relay 4 occupies its lower position.

A circuit isthereupon established from one of the south rails 2 of section A of the track, through the secondary winding 15 of the transformer 5 and contact, member 12 of the relay 4-, to the north rail 2 of the western half of the section of track marked A. The rails 2 of'the western half of the section of the track marked A are then energized with a current of a frequency of 80 cycles. "The rails 2 of the eastern half of the section "of track marked A are not energized when-the relay at occupies its lower'position. Assuming now that a vehicle similar :to the vehicle 7 moves into the deenergized half of the sec tion A of the rails 1,1then there is no voltage impressed upon the primary winding '9 of the transformer 24. Therefore, the transformers 45 and 57 are not energized. Under such operating conditions the relays 7 2 and 'Tiarec'losed. g,

As illustrated when the relays 7 2 and 73 are lVh'e'n either the green lamp 68 or yellow lamp '69 is lighted, the corresponding closed, a lighting circuit for the lamp- 70 is established, whichextendes from the battery 71 through conductor 126, relay .73, conductor 127 relay 72,-lamp 70 back to the battery.

1 When the vehicle? has traveledinto section G, the relay 4a occupies its lower position, therebyestablishinga circuit from the transformer 5a, tl irouglrconta'ct member 12 of the relayfla, to a rail 2 of the western half of section B. 'The rails of the western'half of section B are thereby energized with a currentof cycles frequency. The rails 2 of the eastern half of section B are de-energized, Fig. 1 illu' strating'the position of relay 4a under the conditionsas'sumed.

' The operation of my control system-is such that, when the opposite rails 1 are not ener gized, the brakes are applied and thered-light 70, illustratedin Fig. '2 of the drawing,- is

lighted. lVhenthe opposite rails 1 are-enen gizecl with La current of 80 'cycles'frequency, the brakes are not applied unless the speed'is relatively high. At such time, the yellow lamp 69'is lighted to warn theengineerto exercise caution. Thereforegif another vehic'le approaches section G of the track 1,-its automatic control apparatus will be energized in the first half o fse'ction B by a. current of 80 cycles, thereby energizing the lamp 69 and applying the brakes, if the speed-is too high, to bring the't-ra-in tov a safe stop within the proper lap of distance. I I

When the vehicle "7 occupies section C of the track, the relay 4a occupies its lower position,

thereby energizing the western half of sec-j tion B with acurrent of 80 cycles frequency,

the relay l ofsectionB occupies its upper position by reason of the'energizationb-f its actuating coil. l Vhen the relaylof section B occupies its upper positioma circuit is es tablished from-the south rail2, through the:

secondary winding. 18 of the-transformer '6,

contact member l l of the'relay 4, to north rail 2 of the eastern half of section Af'The rails '2 of section A, consequently,"are enere gized with a currentof 40 cycles:

The rails of the western half of section are also energized with an electrical current of 40'cycles, by means of a circuit that is es- 'tablished from the south rail 2 of section A,

through-the secondary winding 1-18 of the transformer 6 and contact-member 13 of the relay 4, to the 'northrail 2 of the western half of section A. In. other words, in all-sections of track which are unoccupied.byfvehicles, the normal electrical condition of the rails is that they are energized by a current of 4E0 cycles, which indicates that the track is clear. However, in a section of track justbehind a section of track is completely "d-eenergized,

which sets in operation the control system of the vehicle to bring it to a stop. The rails of the remainder of the same section are energized by a current of 80 cycles, which indi- .cates that v the vehicle is approaching another Referring to Fig. 2 ofthedrawing, the auxiliary transformer, 24 is energized'normally by acurrent of 40 cycles traversing gization of the green lamp 68, actuating coil of therelay-72, and actuating coil 42a of the control device 33. The energiza-tion of the V actuating coil of the'relay 7 2 effects the open- '70. The energization of. the actuating coil ingthereofithus de-energizing the red lamp 42a actuates. thesolenoid 41 to the left, thereby closing thepneumatic valve device '26. Inother words, when the coil. 42a is energized, the next section of track 1 is clear, .and" there is no necessity for automatically applying the air. brakes. V

When the current traversing thetaxle 9 i'sof 80 cycles frequency, the secondary winding 67 ofthe auxiliary transformer'24, and hence the primary winding 58 ot the transformer 57, is energized with a current of 80 cycles frequency; When the primary wind- .ingI58'is energized, the secondary winding 59of1the transformer 57, and hence the yellow-lamp 69, actuating coil of the relay, 73 and actuating coil 56.of the electrical device i Ht 54 are energized,

I When the yellow lamp 69 energized, it indicates that theengineer should use can- 'tion inapproachingthe next section of track.

Whenthe relay 73 occupies its upper position, the red lamp 70 is tie-energized. \Vhen (the actuating coil 56 of the electrical device 54 is energized, it tends to actuate the core 55 0f the relay 54-to the left, thereby actuating the'lever35, rod 34 and lever 32 to effect y no 'the closureof the air-brake valve device-26.

Whether-or notthe air-brake valve device 26 is'maintained closed by the .energization of the coil 56 of theelectrical device 54, de-

.-pends upon the degree of energi'zation of the coil 42 of the automatic control device 33.

The. energization of the coil 42 is directly proportional tothespeed at which the genorator 43 is driven. In Other words, if the vehicle is traveling at a high rate of speed, the coil 42 will be energized sufliciently to open the brake valve26and apply the brakes. When thevehicle :is broughtbelow a predetermined speed, the energization ofthe coil 42 is sufiiciently diminished to permit the electrical device 54 to close the valve 26.

When no electrical current is traversing "the axle 9, the transformer 24 is de -energized and, hence, bothtransformers 45 and 57 are "also .de-energized. When both-thetrans formers 45 and57 are de-energized,the signal lamps 68 and 69,.and the actuating coils of the relays '72 and 7 darelikewise de-energized. r

When both relays .72 and. 7 3' are, de-energized, they occupy their closed positions and establish a circuit from the storage battery 71, through the red lamp '70 and the contact members oi the-relays 72 and 7 3- to the battery 71, thereby lighting the red lamp The engineer is given warning, when the red lamp is lighted that hermustapply' the brakes, as his vehicle is within lapfl tance, or less, of an occupied block. '7 lVhen the transformers 45 and 57 are deen'ergized the actuating coils 42av of the control device 33 and-the coil 56. of-the elec- S5 'trical device 54'are de-energized, thereby pern-itting the actuating coil 42 and the resilient member .38 to actuate the pneumatic-brakevalve device 26to its open position, thus causing the brakes of the vehicle 7 'tobe applied. I v Referring to Fig. 5 of the drawing, a plurality of sections .1), E and F of the track are insulated, one from another, by means of insulatedjoints 3. An insulated joint 3 is also provided in the north rail 2 of the track and corresponding transformers 77 and 78 are provided for different sections of track. Electrical constant current dev1ces'79de- 'signed in accordance with the principle of i the monocyclic souiare are provided vfor energizing each of the transformers 77 and 78.

- Each of the electrical devices 79 comprises a plurality of condensers S1 and a plurality of inductance coils'82, all arranged, in the ,form of a square with the condensers 81- on opposite sides ofthe square. The monocyclic square as formed by the condensers 81 and lnductance co1ls'82-1s well understood-in the 1 at lap distance from. the east end of the sections; Correspondingrelays 75' and 76 lllU art, and its operation isfully described in many electrical engineering text books. The

purpose of the electrical. device 79 is to secure,

from a source of electrical currentof constant voltage, current of an approximately '00!!- stant'value for energizing the rails 2. Each of the. transformers 77 and 78 comprises a primary. winding 83, a secondary winding 84, and amagnetlzable core member 85.

The operation of the control system for energizing the trackl, when the vehicle occupiesa section of the track 1, such, for example, as F, is as follows 5 The actuating coil of the relay 76 is short-circuited through the vehicle, thereby causing the relay'- 76 ,to occupy its lower or open position, Therails .2 of the lap portion ofsection E ofthe track 1 are de-energized, thereby so influencing the control system of any following vehicle as to bring it to a stop. ,lVhen the relay76 occupies its closed position, the rails 2 of the lappor tion of section E are energized, andthe relay operates I the automatic control and signal system of the vehicle to indicate that the next sectionin advance is clear of vehicle trai'fic.

Referring to Fig. 6 of the drawing,an auxiliary transformer 86, which is mounted-upon the vehicle 7 comprises an axle 87 that constitutes the primary winding thereof, and a secondary winding 88 whichis slightly removed trom the axle 87. The secondary.

Winding 88 of the transformer 86 iselectrically connected in series relation with the actuating coil ofthe relay 89. -A plurality of lamps 91 and 92, correspondingto danger (red) and clean (green), are provided for indicating to the engineer the .conditionfof the trafiic in the section of track 1 overwhich the vehicleis proceeding.

A pneumatic-brake-valve device 26, which is like the brake-valve device. 26 of Fig. 1, controls the fluid pressure that governs the operation of the air brakes (not illustrated) of the vehicle 7.v The operation of the pneumatic brake valve device 26 is governed'by' a pneu-matlc englne 93 and. an electro-pneu matic valve mechanism 94.

' into an upper chamber 1 '0'3,' middle chamber; 104, and lower chamber 105. The'upper towards. the right.

The pneumatic engine 93 com-prisesa cylin-"- der-95 and a piston 96for actuating a rod 97., which is mechanically connectedto the lever arm. 32 of the brake valve device 26. The

pneumatic engine 93 isprovided with a cylins der 98, in which is mounted ajmovable piston 99. The. piston 99. is. mechanically connected totherod 97 whichis pivotally connected to v the lever. arm 32.

The cylinder '95 is connected to. the trainline pipe 101. thereby causing. fluid pressure to be applied. to the piston 96 to actuate it The movement of the piston 96: causes the rod 97 to actuatethe brake-valved'evice 26to its open position to" effect an application Of' 'tl18 air brakesresilient member or spring 102 is so posle' tioned upon the rod'97 that it tends to actuw ate. the rotatable. member 27. of the brakevalve device 26'to .its closediposition' sothat the brakes may be-released.

The fluid pressure supplied piston 96. to the right and to overcome the resistance of the resili ent member 10:2. However, when pressure is brought to bear against the piston 99, the rod 97 .is actuated to the left. The electropneu-matic valve 94 is divided chamber 103 is connected to a suitable source of fiuidpressure 106 and to the middleIchamher 104 by mea-ns of an opening or port 107 The middlechamber 104 isv pneumatically connectedt'othelower chamber 105 by means of an opening or p'ort108. The lower chamher 105 is connected to the outer'atmosphere by means oi anexhaust pipe 109. The port 8 from ther line. pipe 101 .is sufiicient t actuate. e

107 Y may be closed by-avalvemember 111 I which is mounted upon the rod 112-.:; The port 108 may be closed by a-valve member 113 which is mounted upon the rod 112. The? -valve member ;111-is biase'd'to-itsupper or closed position, and the valve member l13is biased to 1ts upper oropen posit on by means of: a resil ent member .or spring 114. I

The rod 112ma-y be actuated downwardly by means of a magnetizable core member and an actuating coil11G. The cylinder 98 is pneumatically connected to the middle chamber 104 of the electro-pneumatic valve 94-by means of; a pipe 117. Theconstruction of electro-pneumatic valve 94' issuch that, when the actuating-coil 116 is de energi ed,

thefvalve member 113 occupies its open posi;

tion, and fluid, under pressure in the cylinder. '98, is exhausted, through thepipe 117, cha1nbers 104 and105 and exhaust pipe 109 to 'the outeratmosphere. 1 When the fluidun'der pressure in the cylinder 98 is released, the fluid pressure against.

the piston 96 actuatesthe rod 97 to the; right, thereby effecting the, opening of. the valve o1.thevehicle,7. v

When the actuating the core 115 is actuated downwardly and fluid, under pressure, passes from the supply pipe 106 through the upper chamber 103, port I 107, middlccham'ber 104 and pipe 117,. to thef cylinder 98. The fluid pressure upon the piston. 99 actuates" the rod member 97 to. the. lcfl t, thereby closing the brake valve device 2-6 and permitting the brakes to be released.

"device 26, and thus applying the air brakes.

coil 116 is energizech,

hQldingQreIILy H S anda reset -.pi ish but-.

ton 119.; are provided for. thepurpose ofmak ing possible the release of the brakes,only" after the train has come. to, atulljstop. The

is mounted upon the vehicle 7, and, theree fore, the actuating coil ot the 'rela-y '89- are also} de-cnergized and, consequently, the dropsto'its lower position. y f p When the relay 89-occupies its lower posi: tion, a circuit is-established from the source of electrical energy? marked Battery? through thecontact member 123 of-therelay seem];

relay 89 1 red signal lamp 91 to the opposite terminal I gi z edwhen the relay 89:oconpies. its lowerpo- V of-the battery, The actuatingcoi-l; 116 ofithe electro-pneumatic valve 94' is also,'de-cner.-.

sitionas will later appear,tliereby permittin the valve member 111 to occupy its closed position and the valvemember 113 to occupy its en position to thus effect the release of "the uid pressure from the piston 99.

When the fluid pressure-upon the piston 99 is discontinued, theirodmember 97 isactuated by the piston 96 in a counter-clockwise direction, thereby actuating the'brake-valve device 26 to its open position. As stated previously,.when the brake valve device 26 occupies its open position, the brakes of the vehicle 7 are actuated to'bring it to-a stop.- Ifthe engineer desires to operate the vehicle "7 slowly throu h this section of track, he

must dismount from his cab (not illustrated) and press the push-button 119. When'the push-button11'9 is pressed, a circuitis es tablished from the positive terminal of the batter through the contact member 123 of the relay 89, actuating coil of the relay 118 and push-button 119, to the negative terminal of the battery. r

Further, upon the actuation of'therelav 118, a holding circuit is established which I extends from the battery-through conductor 128, contac'tmember 123, conductor 129, the actuating coil of the relay 118, contact mem- V her 124i1nd the conductor 130 back to the batvalve device 26 is a'ctuated'to its closed position, thereby permitting the release of the brakes of the vehicle 7. I

'When the rails 2 over which the vehicle 7 is traveling are electrically energized, a cur rent is induced by means of the transformer 86 into the actuating coil of the" relay 89.

'When theactuating coil of the'r'elay 89 is energized, the contact members 121 to 123,

inclusive, of the relay 89 are actuated to their upper position thereby interrupting: any cir- V 'cuitsthat were established through the contact member 123. The opening of the contact member 123 effects the cle-energizationv of the actuating coil of the relay 118 and of the red lamp591. When the relay 118 is deenergized, the holding circuit throughthe contact Inember'124 of the relay 118 is broken,

if it has been established. V o ,When'the contact members'of the relay89' occupy their upper positions, the green lamp 92, which indicates a clear track, is energized by a circuitthat' is established from thesource of electrical energy marked"Battery through the-contact member 122 of the relay 89 and green lamp 92 to the negative terminal of the battery. I

W n-the contact members 121 to 123, in

elusive, of therelay 89 occupy their-upper positions, the actuating coil 116 of the electropneumatic valve 94 is energized by. a circuit that is established from, the positive terminal of t-he battery through actuating Icoil 116 of the electro-pneumatic valve 94 andcontact member 121 of the relay device 89, to the negative terminal of the battery As stated heretofore, when relay device 116' is energized,; fluid pressure from the supply pipe 106 is applied tot-he piston 99, thereby actuating the brake-valve device 26' to its closed position, whereby the vehicle brakes are maintained 'in released posit-ion; 5

From the above description, that I have provided a control system for antomatically governing the speed of a vehiclein accordance with trafiic conditions on the track over which the vehicle is operating. I have also providedmeans for signaling to the engineer ivhetherhis vehicle is operating on a 5 clear track or Whether he should lower its speed in view OfhlS vehicle approaching another vehicle Within SPCClllGCl l1m1ts tor Whether he should bring his vehicle to a stop..- 'VVhile I have illustratedand described my inventionin its preferred form, it is apparent that minor modifications may be made in'the arrangement of circuits and apparatus em-. ployed Without departing from the spirit of my invention. I desire, therefore, to be limby the scope of the appended claims;

ited only i I claim as my'invent-ion: '1; In an automatictrain control system, the combination With a vehicle having a plurality of axles, of an inductance coilmounted adj acent to one of said axles, braking means comprising a pneumatic valve devlce for braklng said vehicle, means comprising a generator dependent upon'the speed of said vehicle for governing said braking means and means comprising a plurality of actuating coils for selectively governing said vehicle in accordance With frequency of the current traversing said coil. V

2. In an automatic traincontrolsystem, the

combination with; a'railw'ay vehicle, of means comprising a pneumatic valve device for braking said vehicle, a rod for actuating said valve device, a solenoid mounted upon said rod, a

plurality of coils for actuating said solenoidit is apparentin different direct-ions,'means comprising a:

generator-for energizing'one of said coils,

'means comprising a transformer and an inf-1 duct-a-nce' coil for energizing another-of said I actuating coils, means comprising a lever and a third actuating coil for act-uat-ing said rod, means comprising "a second transformer and the same'inductance jcoil for energizing said third actuating coil, and means comprising a reactance device for selectively energizing said transformers in accordancewith 'the frequency of the current-traversing said in-- duct-ance coil, 1 j

3. The combination Witha vehicle having an axle, of means comprising an annular iron core member for preventing or impeding the flow of electrical energy through said axle.

4:. The combination With a vehiclehaving an axle, of means comprising a laminated'animpeding the flow of electrical energy through said axle.

7. The combination With a track having a plurality'of rails, of means for electrically insulating groups of said rails to form sectionsand subsections of track, a plurality ofsources of electricalenergy of different frequencies, and means for selectively connecting said groups of rails to said sources of electrical energy in'accordance With traffic conditions.

8. In a train control system in combination, a plurality of insulated track sections, a ve hicle provided with a plurality of truck axles adapted to travel on the track, means for energizing the track sections, means for utilizing one of the. axles for collecting energy from the track for operating purposes and means for impeding the flow of current in the other axles. I 1

' In testimony whereof, I have hereunto subscribed my name this 20th day of January, 1925. v

'- HARRY M. RYDER. 

